Deadline: An old friend of Oliver Queen’s showed up tonight in Star City to help bring a deceased soul back from beyond. With that mix of the mystical and the bow, the introduction of John Constantine to Arrow is yet another reach into the greater DC Universe that the Warner Bros TV-produced show is making. However, unlike the introduction of The Flash and what will soon be the Legends Of Tomorrow, Constantine showing up on Arrow is more of a rebirth. The Alan Moore co-created demon hunting character from the classic Hellblazer comics saw his own NBC series formally cancelled earlier this year after 13-episodes and no traction in the ratings.